论文部分内容阅读
通过连续提取实验 ,将黄土和古土壤中元素的赋存状态分成六种形态 :水可溶态、可交换态、碳酸盐结合态、铁锰氧化物结合态、有机物结合态和残留态。结果表明 ,K和Rb等元素 ,主要赋存于残留态中 ,而Ca、Sr等元素主要赋存于碳酸盐结合态和残留态中。Sr在黄土和古土壤中的赋存状态明显与Ca的分布有关。在风化成壤作用中 ,碳酸盐的淋溶和含Ca硅酸盐矿物的分解 ,引起Sr的淋失 ,而Rb保持稳定。因此 ,Rb Sr值指示了黄土和古土壤遭受的淋溶程度 ,反映了黄土高原的降雨量 ,是夏季风强度变化的替代性指标
Through successive extraction experiments, the occurrence state of elements in loess and paleosol was divided into six forms: water soluble, exchangeable, carbonate bound, Fe-Mn oxide bound, organic bound and residual. The results show that K, Rb and other elements mainly occur in the residual state, while Ca, Sr and other elements mainly occur in the carbonate-bound and residual states. The occurrence of Sr in loess and paleosol is obviously related to the distribution of Ca. In weathered pedogenesis, carbonate leaching and decomposition of Ca-containing silicate minerals cause leaching of Sr while Rb remains stable. Therefore, the value of Rb Sr indicates the degree of leaching suffered by loess and paleosol, which reflects the rainfall in the Loess Plateau and is an alternative indicator of the intensity of the summer monsoon